YMF744B ETC [List of Unclassifed Manufacturers], YMF744B Datasheet - Page 20

• Manufacturer Part Number: YMF744B
• Description: DS-1S
• Manufacturer: ETC [List of Unclassifed Manufacturers]

YMF744B
42-43h: Extended Legacy Audio Control
b14..............SIEN: Serialized IRQ enable
b15..............LAD: Legacy Audio Disable
b8................MAIM: MPU401 Acknowledge Interrupt Mask
b[12:11] ......SMOD: SB DMA mode
IMOD
DS-1S supports 3 types of interrupt protocols: PCI interrupt (INTA#), Legacy interrupt (IRQs) and
Serialized IRQ. The interrupt protocol is selected with IMOD and SIEN as follows.
The interrupt channels for IRQs and Serialized IRQ are determined by SBIRQ and MPUIRQ,. Only one
protocol can be used at once.
This bit disables the Legacy Audio block.
When this bit is set to “1”, DS-1S does not respond to the I/O Target transaction for legacy I/O address on
the PCI bus.
This bit determine whether interrupt is asserted when the acknowledge, which is occurred by changing
MPU401 mode form default to UART, is returned.
These bits determine the protocol to achieve the DMAC(8237) function on the PCI bus.
b15
“0”: Enables the Legacy Audio block
“1”: Disables the Legacy Audio block
“0”: Interrupt is asserted when the acknowledge is returned.
“1”: Interrupt is masked when the acknowledge is returned.
“0”:
“1”:
“2”:
“3”
Read / Write
Default: 0000h
Access Bus Width: 8, 16, 32-bit
SIEN
0
0
1
b14
SBVER
IMOD
b13
PC/PCI
reserved
Distributed DMA
reserved
0
1
*
b12
SMOD
Interrupt protocol
Legacy interrupt (IRQs)
PCI interrupt (INTA#)
Serialized IRQ
b11
(default)
b10
-
b9
-
(default)
-20-
MAIM
b8
b7
(default)
-
b6
-
(default)
b5
-
b4
-
b3
-
February 3, 1999
b2
-
b1
-
b0
-